EcoVent: Make every room in your home the right temperature [video] | Hacker News Reader

EcoVent: Make every room in your home the right temperature [video]

get.ecoventsystems.com

61 pointsph0rque28 comments

I'd love to see more information on the product. Like my profile says, I worked at an HVAC optimization company a few years back. We played with the idea of adding wireless vents to control flow, but parkrrr mentioned we were concerned about pressure, along with not getting permission from our clients to swap there vents. Most of our clients had anywhere from 2 HVAC units controlling the building (most fast food chains), up to 40 (for a massive office we installed in). Depending on the building size and the number of individual 'zones' a given HVAC unit has to hit, it was almost impossible. We ran into issues where no matter what our system did, it would just not cool the kitchen below 95°F. Granted, the owners of these chains were incredibly frugal, often buying the cheapest option no matter what (plus we'd sold many of the systems on false promises before our original CEO left the company).

What is ecoVent using to manage communication? Long-range bluetooth, WiFi, Zigbee or Z-Wave? What kind of communication do you have going on in general? If you're looking into any 'performance' monitoring, but leaving the company I was in charge of developing an "early alert" system that would alert you to when the unit had degraded to the point of repair (before breaking). Since the old company's been defunct for years now, I don't see any conflict sharing the IP.

hey man, please reach out to me dp[at]ecoventsystems [dot]com. Would love to chat with you.

Thanks!

Is there any chance you can address parker's, tsumnia's or joezydeco's concerns publicly? I redid some of my ducts and the contractor and I spent a fair amount of time making sure everything was balanced. Without this experience the importance of balancing the pressure never would have occurred to me.

After reading the LBNL study mentioned in ecovent's whitepaper I do not know what is going on here. The LBNL study concludes:

  The closing  of registers led to  an increase in energy  use for the
  typical California  house and  duct system  used in  this study. The
  reduction in building load due  to not conditioning the entire house
  was more than  offset by increased duct system losses  mostly due to
  increased duct leakage.

  The  register closing  technique has  less impact  on energy  use if
  registers furthest  from the  air handler  are closed  first because
  this tends  to only  affect the  pressures and  air leakage  for the
  closed off branch. Closing registers nearer the air handler tends to
  increase the pressures and air leakage for the whole system.

  Closing  too  many registers  (more  than  60%) is  not  recommended
  because the  added flow resistance  severely restricts the  air flow
  though the  system to the  point where  furnaces may operate  on the
  high-limit switch and cooling systems may suffer from frozen coils.

Hi, I'm one of the co-founders of ecovent. The LBNL study did not address systems that can monitor their impact on an HVAC system. Some homes have leaky ducts and some have very tight ducts. The only way to tell is to measure them. Our system does measure it's impact, and maximizes the comfort and savings available for a given system. We can also provide suggestions for improving your home, such as rooms that need insulation or ducts that are very leaky. The same principle applies to reducing the airflow too much with respect to high limit switches and coil freezing. We monitor and adapt to the situation. Please let us know if you have more questions.

There was a different approach to this called the "MyTemp system" [1] by a company called "Home Comfort Zones".

Home Comfort Zones has been acquired by a company called "Emme E2MS LLC" [2].

The MyTemp system used pneumatically inflated, vacuum pump deflated "pneumatic damper" devices (balloons, if you will) in the distribution lines. It included plenum sensors for temp and pressure, pumps and hardwired per-room thermostats.

It looked good to me but a system for my home would have cost about $12,000 if I recall correctly (just for the controls added onto an /existing/ system).

With that amount of money, I might have instead have a mini-split variable-rate air conditioning system installed and achieved better savings long term. But both are out of my price range for a retrofit; the target market was very high end.

-----

[1] [PDF] www.mytemperature.com/pdf/MyTemp_for_Existing_Homes.pdf

[2] http://www.getemme.com/homecomfortzones.php

It's my understanding that if you have a forced-air system, closing vents is detrimental due to the pressures involved. Closing the vents adds strain to your blower and redirects the, now higher pressure, air to other parts of the house.

I'm no HVAC guru, this is simply what I've been told. Can someone enlighten me, or how does this technology approach this situation?

hey man, check out the whitepaper here: http://ecoventsystems.com/blog/2014/03/new-whitepaper-when-i...

"Although each of these issues poses problems for traditional HVAC system designs, each of them can be overcome with a combination of advanced software and hardware. [The End.]"

Can you be more specific than that?

Absolutely. Can you reach out to me at dp [at]ecoventsystems [dot]com? Thanks man.

Same idea as http://www.suntulit.com but they never quite launched despite much fanfare. I think they were acquired

The US doesn't like to do too much upfront HVAC costs, and for whatever reason generally just wants something simple. I used to work for a company that resold European systems that seemed to be about greater upfront costs in things like room occupancy sensing, humidity control, airflow analysis of the room, etc, which would've saved a lot of people money but they just didn't want the upfront cost.

Are you referring to residential HVAC systems or commercial ones? In my limited exposure, forced-air systems don't really exist in the majority of European homes. They tend to be radiator-based heating loops with individual thermostatic valves on the radiators. Air conditioning, if it's installed at all, is limited to single-room or area units, not whole-house units.

Zone control is indeed expensive, and I'm definitely interested in Ecovent's idea about putting flow control at the floor vents (or is it just the registers). But unless these units are battery-driven, I see more complexity in just getting the silly things wired up, not to mention making sure doors are closed and pressure is regulated to keep those nasty dust lines from appearing on the carpets under your doors.

> But unless these units are battery-driven, I see more complexity in just getting the silly things wired up

Opening/closing the vent very occasionally shouldn't require more than some AA batteries in each vent. Lithium batteries ($5-8 for a 4-pack) would last months or even years. I have some powering the keypad & deadbolt on my front door, which is both remote controllable like these vents would be, and has to operate a motor to turn the bolt, and it's rated for 1-2 years use on a single set of batteries.

Another thing to note, the vents would only need to be adjusted when the heat load in a particular room changed too much which might mean only slight changes every now and then to adjust air distribution in response to changing seasons or a cold spell. You could still reap tons of benefits by getting the air flow close to optimum and not constantly readjusting to exactly meet the maximum. The video mentioned the vents closing when it reaches the proper temperature but I can't see why they wouldn't also open them partially to save on needless opening and closing vents.

Of course, but I'm also counting in the radio stage of the unit. If it's one-way that's cool, if it's two-way then there are other concerns about power usage.

Yeah it was mostly all commercial, but there were some select few larger residential. I am interested though too in what all could be possible with this device. Pressure is a huge huge consideration especially in factories. Heck they need more consideration in the high rise office I work in now too around pressure, but it is all perhaps an iterative process closer and closer to ideals, and eventually a trade off with cost.

Forced-air systems are on the rise in Europe, mostly due to stricter regulations in regards to energy performance (insulation and ventilation). Many new low-energy homes (and passive houses) now have forced-air systems. You can get tax cuts and other subsidies in some areas.

I would buy one today if it were available. One thing I don't understand is how the vents control when the AC turns on or off. If it can't do that, then I don't see how it will work well.

Edit: It would be easy to do if you replaced the thermostat, but interfacing with legacy ones (or running wire) would be a pain.

You would certainly want to interface with the thermostat but you don't necessarily have to, for instance, you could just open all vents when the AC kicks on except the one by the thermostat and have each room close off when it gets cold enough and open the thermostat vent so that it kicks off around when every other room is cool enough.

Hey man, I'm dip, one of the co-founders of ecovent. You're absolutely right, we need to control the thermostat to maximize the utility of the system. Our plan is to integrate with any wifi thermostat.

If you're interested in joining our beta program, please email me at: dp [at] ecoventsystems [dot] com.

How do you ensure enough air flow? If I blocked off three rooms with my A/C, it would be continually freezing up. I like the concept, but worry about causing strain on the blower because it is trying to push too much air through.

In systems that automate flow to zones using actuated vent dampers, there is always a bypass system that allows extra air flow to cycle back to the intake.

For a system like EcoVent to work with central air, it, ideally, would integrate with the thermostat so that it has context and control to ensure the system does not cycle too much and that that heat exchanger doesn't freeze up.

Easy enough to do but yeah no mention of a thermostat on their page.

How does this handle things like static pressure? If you close too many vents it is actually detrimental to your blower fan and cause damage!

EcoVent should never need to close every single vent in the house, but even if it did, yes the static pressure in the ducts would rise but what is important is the pressure differential around the blower. If you have a totally 100% blocked filter this will cause the highest pressure differential around the blower that the unit will ever see in it's lifetime and it still shouldn't be the blower that's potentially damaged, it should be the evap coils freezing up or liquid refrigerant making it's way back to the compressor and screwing things up, yes there will be more load on the blower motor but I don't see this damaging it unless it's more like a 100% restriction running at 100% duty cycle for a very long period of time causing the motor to burn up.

Heat. If there's no airflow around the blower (and therefore the blower motor which is usually integrated, then the motor will run hotter. Temperature has an inverse relationship with motor lifetime. The hotter it runs, the sooner it will fail. Even if it never exceeds its maximum rated temperature.

I remember you guys from the Beehive days! Congrats on your achievements so far!

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